Molecular dynamics simulations are used to investigate lithium (Li)
transport rates in symmetric tilt graphite grain boundaries (GBs).
Experiments have quantified highly varied diffusion rates of Li in
graphite and recent computational work exposed similar differences in Li
intercalation rates into GBs from a free surface. This work extends
findings of intercalation studies to provide explanations for various
rates and uses said differences to predict bulk GB transport behavior.
Various structural properties are presented for graphite GBs, including
bond angles, bond order, and free volume analysis which is rarely
presented in covalent systems. The importance of free volume
connectivity is also discussed as is Li structure in GBs.